Research Design for print - File Formats

FILE FORMATS

JPEG -

 RGB - 24-bits (8-bit color), Grayscale - 8-bits (only these)

JPEG always uses lossy JPG compression, but its degree is selectable, for higher quality and larger files, or lower quality and smaller files. JPG is for photo images, and is the worst possible choice for most graphics or text data.

TIF -

Versatile, many formats supported.

Mode: RGB or CMYK or LAB, and others, almost anything.

8 or 16-bits per color channel, called 8 or 16-bit "color" (24 or 48-bit RGB files).

Grayscale - 8 or 16-bits, 

GIF-

Indexed color - 1 to 8-bits (8-bit indexes, limiting to only 256 colors maximum.) Color is 24-bit color, but only 256 colors.

GIF uses lossless LZW compression. (for Indexed Color, see second page at GIF link at page bottom).GIF also supports animation, showing several sequential frames fast to simulate motion.

PNG- 

RGB - 24 or 48-bits (called 8-bit or 16-bit "color"),

Alpha channel for RGB transparency - 32 bits

Grayscale - 8 or 16-bits,

Indexed color - 1 to 8-bits,

Line Art (bilevel) - 1-bit

Supports transparency in regular indexed color, and also there can be a fourth channel (called Alpha) which can map RGB graduated transparency (by pixel location, instead of only one color, and graduated, instead of only on or off).

PNG also supports animation (like GIF), showing several sequential frames fast to simulate motion.

PDF-